MELBOURNE, Australia (AP) — Roger Federer kept his cool on a scorching hot second day at the Australian Open, starting his record 57th consecutive Grand Slam tournament with a straight-sets victory in his first competitive match in front of new coach Stefan Edberg.

Federer was the second match on Rod Laver Arena on Tuesday, and the temperature topped 41 Celsius (106 Fahrenheit) during his 6-4, 6-4, 6-2 win over Australian wild-card entry James Duckworth.

Two-time defending women's champion Victoria Azarenka played the previous match on the center court, and said it felt "like you're dancing in a frying pan."

"It was very dry, just hot, stinging sort of sun," he added later. "Depending on where you come from it has a bigger effect on you, this type of heat. So it's very personal, and it can become just a very mental thing — you just can't accept that it's hot."

He now owns the record for playing the most consecutive Grand Slam events, another milestone in a career that has already resulted in 17 major titles for the Swiss star.

He kept the points as short as possible, and only gave No. 133-ranked Duckworth one look at a break point in the 1-hour, 46-minute match.

Federer said Edberg, a childhood hero whom he hired on a part-time basis last month, practiced with him before the match.

"He warmed me up .... I won!"

The heat at Melbourne Park topped 42C (108F) later, and the forecast was for more high temperatures until Friday. It was even hotter in nearby Avalon, which peaked above 45C (113F).

A hot, gusty breeze swirled across Melbourne Park all day, making conditions more challenging instead of cooler. The crowd for the day session was 35,571, almost 12,000 down on day one.

Players draped bags of ice over their necks and shoulders and sat under covered seats in the changeovers. They retreated into the shade at the back of the courts between points.

Spectators covered their heads and shoulders with damp towels to cool off and queued in front of large electric fans blasting water at their faces. A ball kid was treated for heat stress during a morning match.

Some players struggled. Canadian qualifier Frank Dancevic said he blacked out during a 7-6 (12), 6-4, 6-3 loss to No. 27 Benoit Paire of France. Dancevic had treatment in the second set but continued.

He was playing on Court 6, where Polona Hercog retired after one game with an injured shoulder and where No. 13 John Isner, the only seeded American man in the draw, retired with an injured right ankle after losing the first two sets against Martin Klizan.

Czech veteran Radek Stepanek retired with a sore neck in the fourth set against Blaz Kavcic, but said it wasn't heat-related.

By the time top seeded Rafael Nadal took the court he was playing under relatively mild conditions.

Nadal's Australian opponent Bernard Tomic, bothered from the start by a left leg injury, retired from the match after losing the first set 6-4. Some in the capacity crowd of 15,000 at Rod Laver Arena booed lustily when Tomic indicated he could not continue.

"I know how tough is this situation, I had the same a few years ago at this tournament," Nadal said of Tomic's injury. "Since the beginning, I saw a little bit he had some problems on the leg."

In the final match of the day Maria Sharapova defeated the USA's Bethanie Mattek-Sands, 6-3, 6-4.

James O'Grady of court services and operations prepares ice vests and ice filled collars for players ahead of the 2014 Australian Open tennis tournament. Players were woozy and vomiting and a ball kid fainted during the 108 degree temperatures.
William West AFP/Getty Images